So it looks like Facebook finally opened up access to their chat service for third party applications such as Pidgin, Adium, etc..
They used the open protocol XMPP (good for them!) so we can use our regular IM client to chat with our Facebook contacts without the need of ugly hackish plugins.

Instructions for Pidgin (version 2.7):

- Get a Facebook username. We have a numerical one by default (which we won't know unless someone with his/her account set up in Pidgin tells us) but in the Account Setting menu we can set a new one (for example, alias.surname)

- Create a new account in Pidgin with the Account Manager. Parameters:
Protocol: XMPP
User name: alias.surname (the one chose above)
Domain: chat.facebook.com
Resource: Facebook (whatever label, really)
Password: Our facebook's password (duh!)
ADVANCED TAB:
Disable 'Require SSL/TLS encryption'
Connect to server: chat.facebook.com

Sources:
http://wiki.developers.facebook.com/..._Facebook_Chat
http://www.facebook.com/sitetour/chat.php




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